Satellites in effort to save the world’s coral reefs (Reports)

Sediment runoff is not only a direct threat to the Great Barrier Reef, but is affecting how coral recovers from other threats, new international research has found.

A joint study by the Canadian Dalhousie University along with James Cook University’s ARC Centre of Excellence for Coral Reef Studies and the University of Adelaide analysed 20 years of satellite footage of the southern end of the reef.

The study’s co-author, JCU PhD candidate Sam Matthews, said they found the coral in areas affected by regular runoff recovered more slowly than the coral in more pristine areas.

“Improving water quality is something that’s going to do a lot of good for the Great Barrier Reef,” Mr Matthews said.

“Our results provide strong support for government policies aimed at reducing nutrient pollution to help increase the resilience of the Great Barrier Reef, in recovering from damage due to tropical cyclones, crown-of-thorns outbreaks and coral bleaching.”

The study found that an improvement of between 6 and 17 per cent in water quality may buffer the predicted increases in coral bleaching at some inshore locations.

That level of improvement is within the scope of the government’s improvement plans, but the Australian Marine Conservation Society Great Barrier Reef campaign manager Lissa Schindler said the targets are unlikely to be met.

“There is concern that they’re running out of time to meet those targets, because the first set of deadlines in 2025 and it’s 2019 now,” Dr Schindler said.

“So we really need the government to rapidly put these laws through parliament and then enforce them.”

Water sediment affected reefs closer to the shore more than those further out, the study found.